Concept
Frame of reference
Overview
In physics and astronomy, a frame of reference (or reference frame) is an abstract coordinate system, whose origin, orientation, and scale have been specified in physical space. It is based on a set of reference points, defined as geometric points whose position is identified both mathematically (with numerical coordinate values) and physically (signaled by conventional markers).
An important special case is that of an inertial reference frame, a stationary or uniformly moving frame.
For n dimensions, n + 1 reference points are sufficient to fully define a reference frame. Using rectangular Cartesian coordinates, a reference frame may be defined with a reference point at the origin and a reference point at one unit distance from the origin along each of the n coordinate axes.
In Einsteinian relativity, reference frames are used to specify the relationship between a moving observer and the phenomenon under observation. In this context, the term often becomes observational frame of reference (or observational reference frame), which implies that the observer is at rest in the frame, although not necessarily located at its origin. A relativistic reference frame includes (or implies) the coordinate time, which does not equate across different reference frames moving relatively to each other. The situation thus differs from Galilean relativity, in which all possible coordinate times are essentially equivalent.
Overview adapted from Wikipedia (CC BY-SA 4.0; see the article history for authors).
Possible passages
Found by search and not yet checked by a person; they may only mention the idea in passing.
The axiom can be explained as follows: Let {alpha} and {beta} be the names of two time-systems. The directions of motion in the space of {alpha} due to rest in a point of {beta} is called the '{beta}-direction in {alpha}' and the direction of motion in the space of {beta} due to rest in a point of {alpha} is called the '{alpha}-direction in {beta}.' Consider a motion in the space of {alpha} consisting of a certain…
Alfred North Whitehead, The Concept of Nature The Tarner Lectures Delivered in Trinity College, November 1919
States what Frame of reference is.
It may be observed that the introduction of "local time" suggested by the principle of relativity has effected, for purely scientific reasons, much the same multiplication of times as we have just been advocating. The sum-total of all the particulars that are (directly) either simultaneous with or before or after a given particular may be defined as the "biography" to which that particular belongs. It will be…
Bertrand Russell, Mysticism and Logic and Other Essays
States what Frame of reference is.
Congruence was to refer to geometrical bodies, with none of the properties of ordinary bodies except impenetrability (Erdmann, Axiome der Geometrie, p. 26). A straight line is defined as determined by two of its points[14], and a plane as determined by three. These premisses, with a slight exception as to the straight line, we shall hereafter find essential to every Geometry. I have drawn attention to them, as it is…
Bertrand Russell, An essay on the foundations of geometry
States what Frame of reference is.
Related ideas
- General relativity
- Algebra
- Axiomatic system
- Geometry
- Classical mechanics
- Maxwell's equations
- Model theory
- Manifold
- Physics
- Particle physics
- Quantum field theory
- Quantum gravity
- Second
- Special relativity
- Space
- Galilean invariance
- Speed
- Spacetime
- Theory of relativity
- Vacuum
- Standard Model
- Astronomy
- Fourier series
- Measurement problem
Place in the tradition
Part of Deductive-nomological model.